Broaching-die.



W. R. WALKER.

BROAGHING DIE.

APPLICATION FILED MAR.14, 1911.

Patented Aug. 19, 1913*.

VIII/[11.71431 j A220 rney.

UNITED STATES WILLARD R. WALKER, OF SYRACUSE, NEW YORK.

BBOACHING-DIE.

Specification of Letters Patent.

Patented. Aug. 19,1913.

Application filed March 14, 1911. Serial No. 614,421.

To all whom it may concern:

Be it known that I, WILLARD R. WALKnR, of Syracuse, in the county ofOnondaga, 1n the State of New York, have invented new and usefulImprovements in Broachmg- Dies, of which the following, taken nconnection with the accompanying drawings, 1s a full, clear, and exact(18801113131011.-

This invention relates to certain improvements in channeling diesforgrooving nuts and similar articles which may be forced through the diesunder pressure of a suitable plunger, the specific object b6111 to formlengthwise grooves in the sides oi lock nuts for receiving suitablelocking keys or pins somewhat similar to that set forth in my Patent#761,274, issued May 31, 1904, in which the key is passed through anaperture in the bolt and its ends bentover into the grooves in the nutto lock the nut and bolt against relative turning.

The main object is to cut a plurality of four or more grooves in thesides of a nut in pairs diametrically opposite to each other 1 in asingle operatlon, the number of grooves depending upon the number ofsides of the nut.

In my pending application #376,186 filed May 28, 1907, is shown adie'having stepped groove cutters for cutting the grooves graduallydeeper as the nut is forced through the die but in that case the cuttersare formed upon disks which are seated one upon the other in the diesupporting block. These disks are, however, not only difficult andexpensive to make but it is found to be practically impossible to obtaina uniform hardening of the cutters, some of which will be too brittleand others too soft, and furthermore in these disk dies or cutters allof the cutting edges of the-cutters are disposed in substantiallythesame plane at right angles to the axis of the die so that the cutters ofeach disk are cutting atthe same time, thereby requiring a considerablepower to force the nut through the die and also producing excessivestrain upon such die. Another serious objection to the. use of thesedisk dies is that'the sudden passage of the nut under pressure from onedisk to the next succeeding disk is more or less liable to break thecutters. A still further objection to the use of disk cutters is thatthe cutters of each disk must be milled separately by reason of the factthat they are of elifierent radial depth than those of the other disks.

The object of my present invention is to overcome these ObJBClZlOIlS;first, by making all of the stepped cutters for grooving one side of thenut upon a single, bar which may be easily tempered to the desiredhardness; second, by permltting a large number of these bars to beplaced together side bV side and their cutters milled in the edgesthereof simultaneously; and third, by permitting the cutter bars to bearranged in the die block in such manner that the corresponding cuttinedges of each diametrically opposite pair 0 bars maybe disposed insubstantially the same transverse plane but in a different plane fromthe corresponding cutting edges of the other diametrically oppositepairs so that the corresponding cutting edges of one pair are in adifferent plane from those of the next adjacent pair, wherebythe cuttingof the grooves is more gradual and with less resistance than would bethe case if the corresponding cutting edges were in the same plane.

Another object is to make the die block of side and end sections so thatthe sides may be quickly and economically grooved for the reception ofcutter bars, and'to-construct the end sections in such manner that theyserve to lock the side sections together and also to retain the cutterbars firmly in operative position, thereby permitting either one or allof the cutter bars to beremoved or withdrawn'endwise by simply removingone of the end heads or sections.

Other objects and uses will be brought out in the following description:

In the drawings-Figure l is a top plan of my improved die. Figs. 2' and'3 are transverse vertical sectional views taken respectively on lines2-2 and 3-3 Fig. 1. Fig. 4 is a horizontal sectional viewtaken on'lineM, Fig. 3 except that both side sections of the die block are shown.Figs. 5 and 6 are respectively a side elevation and anedge view of oneof the cutter bars. Fig. 7 is a lengthwise sectional view through thecutting teeth of a portion of one of the bars taken on line 7-7, Fig. 5.Figs. 8 and 9 are transverse sectional views taken res ectively on lines8-8 and 9-9 Fig. 5. ig. 10 is a top plan of a groove nut after being cutby my improved die.

This die preferably consists eta substantially rectangular sectionalblock of cast metal, -maehine steel or othersuitable material composedcit-opposite similar side set tions, -1- opposite end sections --2-- and-3- and a series of, m this mstance SIX,

' similar cutter'bars -4 for groovin hexform a hollow rectangular block,substantially' square in cross section as shown in Fi -4, each sectionbeing of substantia y the same form and size and provlded with a seriesof, in this instance three, substantially radial, lengthwise grooves -5extending from end to end of the sections -1 and spaced a uniformdistance apart around a'eommon axis to form suitable seats for thecutter bars I The end sections 2- and 3-- are provided withsubstantially central openings '--6 and 7- coaxial with each otherandwith the opening between the sections 1, the opening -6 being preferablycircular and somewhat larger than the opening -7-, which latter ispreferably hexangular or of substantiall the same form and size as thenut whic is to be grooved and through which said nut is adapted to beforced under pressure of a plunger 8- shown by dotted lines in Fig.-2--.

The upper side of the head -3 is provided with a radial guide groove orrecess 9 extending from the opening -7 to one side of the head into andalong which the nut may be inserted and moved inwardly to register withthe opening -7- preparatory to cutting the grooves therein 1n a mannerhereinafter described.

The base or head 2- is provided with an annular groove -10-'- concentricwith the opening 6 for forming inner and outer --ing inner and outerflanges or shoulders.

i the block in sections is to shoulders or flanges 11- and'12- forreceiving reduced projections or flanges -13 on the adjacent end of thesections -1- and thereby locking said sections against relative radialmovement, said head being additionally secured to the sections 1-- byscrews 14 shown by dotted lines in Figs. 2; and 3. In like mannertheopposite head 3- is secured to the adjacent end of the sections --1-by screws --15" also shown by dotted lines in Figs. -2- and 3-, saidhead being provided with an annular groove 16- concentric with the axisof the opening --7 and form- 17- and -18- fdr receiving the reducedadjacent ends 19 of the sections --1 and thereby locking the upper endsof said sections against relative radial movement in a manner similar tothat described for the base sections 2-.

The object in making the main body of permit the grooves -4 to be moreeas1 y and acgradually curately milled or formed from the inside whichoperation may be performed by simly running the milling or planing toolenigthwise of the sections -1 from end to en and In order that theintermediate portions may der the hi hpressure required to orce the nutthrong the die in the operation of cutting the groove, said intermediateportions are secured together by belts or machine screws 20- as bestseen in Fig. 4'.

The cutter bars 4 are preferably made of stock steel suitably hardenedto resist the strains to which they are subjected and are all ofsubstantially the same size and of such thickness as to fit snugly intheir respective grooves so that they may be readily interchangedthereby permitting any one'of the bars to be inserted in any one of thegrooves.

The outer edges of the bars and bases of the grooves against which theyare seated are substantially straight so as to facilitate the insertionand withdrawal of the bars in and from the sections 1- and at the sametime rigidly sustaining said bars at all points to prevent them fromspringing lat erally under pressure to which they are subjected inforcing the nut through the die.

The inner edges of the main body of the cutter bars pro ect inwardlysome distance beyond the grooves in which they are seated or rather intothe openin between the sections 1- and are pre erably reduced inthickness and provided with a series of teeth 21- of graduallyincreasing radial depth from the head end -3 toward the opposite endsection --2 so that each succeeding tooth projects inwardly slightlybeyond the vertical plane of the next one to it to cause the grooves tobe cut in the nut as said nutis forced through the die, thereby takingofi a comparatively light chip or shaving.

It will be observed upon reference to Figs. -3 and -5+ that the inneredge of each tooth is beveled or gradually recedes outwardly from thepoint toward the base and that ,one and the same side faces of theoutting edges of the teeth are also beveled or wardly away from thecutters and through said opening away from the die, thereby avoiding anypossibility of the die becom=,, ing clogged with such chips or shavings.

Each of these 1 shavings to gravitate downwardly and out By arrangingthe cutter bars in the man- 3. A broaching die comprising a hollow blockhaving a plurality of setsof lon tudinally stepped teeth and lengthwisec earing grooves for the chips between the several sets of teeth.

4. A broaching die comprising a hollow block having a plurality 0 setsof longitudinally stepped teeth and lengthwise clearing grooves for thechips between the several sets of teeth, said teeth having lengthwisechannels in one side communicating with the lengthwise grooves fordeflecting the chi s fromthe base of the teeth into said and providedwith chip-clearance channels a hollow channe s.

A breaching die comprising block having a set of grooves for receivingcutter bars and another set of grooves for receiving chips, cutter barsseated in their grooves and having stepped teeth, said teeth havingclearance channels in their sides facing the grooves for' the chips.

6. A broaching die having a lengthwise opening therethrough from end toend and a series of lengthwise channels communicating with said opening,said die being also provided with a plurality of sets of longitudinallystepped teeth projecting into the opening between said channels.

7. A broaching die comprising a main supporting body having a lengthwiseopem ing therethrough from end to end and a lurality of sets of teethprojecting radiall rom the main body into said opening, thh teeth ofeach set being stepped longitudinally from one end toward the oppositeend in their sides and communicating with said opening.

In witness whereof I have hereunto set my hand on this 14th day ofDecember, 1910.

WILLARD R. WALKER. Witnesses:

H. E. CHASE, E. F. SPEAKING.

ner shown in Fig. 4 so that the beveled edges or recesses 22- face asingle groove or clearance channel 23-, it is only necessary to form-half as many of these grooves or channels as there are cutter bars andaside from this-economy of manufacture of the dies, the beveled edges orrecesses 22 together with the grooves 23- constitute an importantfeature of my invention in that the beveled edges 22 operate toautomatically deflect the chips or shavings away from the cutting edgesof the teeth and into the channels 23 which are of sufiicient size toallow said chips to readily gravitate from between the bars downwardlythrough the opening 6- and clear of the die. The cutter bars 4 are alsoprovided with reduced ends 25 which extend into the recesses -10- and-l6 respectively in the lower and upper heads 2- and -3- and fit snuglybetween the bases of the grooves 5 and inner flanges 11 and -l7. Thelength of these reduced portions 25 of the bars -t is substantiallyequal to the depths of the grooves in which they are seated, while theopposite ends of the intermediate portions of the edges of said cutterbars rest against the inner faces of the flanges 1l and 17 therebypreventing any possibility of endwise movement of said bars when theheads are clamped in place upon the sections l.

Another important feature of this invention consists in arranging theteeth of each bar so that the cutting edges of the corresponding teethof adjacent bars are in slightly different horizontal planes whereby thepreceding tooth of one bar will have at least partially out the groovein one side of the nut before the corresponding tooth of the nextadjacent bar begins to cut and so on down through the series of teeth ofthe several bars but the cutting edges of corresponding teeth ofdiametrically opposite bars are preferably disposed in the samehorizontal plane. so as to operate on diametrically opposite sides ofthe nut at the same time, thereby more effectively supporting andguiding the nut in a horizontal plane as it is forced through the die.By this arrangement of the teeth the cutting of the grooves is moregradual and produces less strain upon the die and also requires lesspower to force the nut through the die with less liability to passsuddenly from one set to the next succeeding set of teeth.

In assembling the parts of the broaching die or sections l may first beclamped together by the bolts 20 after which the base sections -2 may besecured in place by the bolts l4 and the cutter bars 4. are then placedin their respective grooves and the upper head 3 secured in place by thescrews -l5, the die being then ready for use.

The nut to be broached or grooved is then placed in the groove -9 andmoved inwardly into registration with the central opening in the die soas to rest upon the uppermost teeth of a pair of diametrically oppositebars. The plunger 8- is then forced downwardly to press the nut throughthe die to form the grooves therein. As the nut is forced from the topdownwardly through the die, the groove is gradually deepened as itencounters the successive teeth which are stepped inwardly from the topdownward. During this operation the chips or shavings which are cut fromthe blank are deflected laterally through the channels -22 in one sideof the cutting edges of the teeth and thence into the grooves 23-through which the chips and shavings gravitate through the opening 6clear from the die, the grooved nuts being also ejected from saidopening.

The die is preferably made of sufficient length to receive a number ofnuts at a time and in order that the grooving operation may beeconomical, the first nut inserted through the inlet -7- is forceddownwardly by the plunger a distance substantially equal to thethickness of the nut, whereupon the plunger is elevated and another nutis inserted and similarly operated upon by the plunger, this operationbeing repeated as each nut is forced downwardly a distance equal to itsthickness so that as the operation progresses the die is substantiallyfilled with nuts and therefore a plurality of them are being cut at thesame time. 7

In case any one of the cutter bars should become impaired by thebreaking of one or more of its teeth, it may be readily withdrawn andreplaced by a new one Without disturbing the other cutter bars by simplyremoving the one or the other of the end heads as, for example, theupper head 3- and afterward replacing it with the assurance that all ofthe bars will be firmly held in fixed relation to the die block whenadjusted for use.

What I claim is:

1. A broaching die having a lengthwise opening therethrough and providedwith a plurality of lengthwise sets of teeth facing the lengthwisecenter of the opening, those of each set being stepped longitudinallytoward said axis and provided with clearance channels in their sidescommunicating with said opening in the die.

2. A hollow broaching die having a plu rality of sets of longitudinallystepped teeth projecting inwardly toward the longitudinal center of thedie and provided with lengthwise clearance channels communicating withthe interior of the die for deflecting the chips to one side of theteeth.

